LS1 or old school small block? - F-Body Road Racing and Autocross Forums

I'm building a 67 RS autocross/track toy that can still be street driven. So far the car has a custom front clip with C5 corvette suspension and a C4 corvette IRS out back. Sitting in the car now is a small block and a NASCAR built super T10

My son blew his LS1 motor on Sat and scooped up a longblock locally, I now have a LS1 at my disposal (if it's rebuildable) Between he and I we have enough take off parts to pretty much make a complete motor minus the accesories.

So here's the question. Should I continue to keep the SBC that's in the car now or go with the LS1?

The SBC is a destroked 400. 4 bolt main, steel crank, wiesco pistions and chevy pink rods. Heads are 441's with 2.02 1.6 valves, fully ported and port matched to the headers and intake. Intake is an old school torquer single plane. Carb is a 650 mech. Estimated power around 425 or so.

LS1 would be a mild build with the usual bolt ons. Custom mega squirt efi controller, maybe put a carb intake on it and use the 650?

I would keep the Super T10 trans (4speed) that I have now in either case.

At this point on the car, I still have to do the fuel system and the wiring so either route logisitcally would be the same.

Anybody know the weight difference between a iron headed SBC and an LS1? What would you guys do if you had the choice?

Beach Cruiser View Member Profile	Feb 22 2011, 06:05 PM Post #1
Advanced Member Group: Advanced Members Posts: 264 Joined: 31-July 07 From: Virginia Beach Member No.: 1,870	I'm building a 67 RS autocross/track toy that can still be street driven. So far the car has a custom front clip with C5 corvette suspension and a C4 corvette IRS out back. Sitting in the car now is a small block and a NASCAR built super T10 My son blew his LS1 motor on Sat and scooped up a longblock locally, I now have a LS1 at my disposal (if it's rebuildable) Between he and I we have enough take off parts to pretty much make a complete motor minus the accesories. So here's the question. Should I continue to keep the SBC that's in the car now or go with the LS1? The SBC is a destroked 400. 4 bolt main, steel crank, wiesco pistions and chevy pink rods. Heads are 441's with 2.02 1.6 valves, fully ported and port matched to the headers and intake. Intake is an old school torquer single plane. Carb is a 650 mech. Estimated power around 425 or so. LS1 would be a mild build with the usual bolt ons. Custom mega squirt efi controller, maybe put a carb intake on it and use the 650? I would keep the Super T10 trans (4speed) that I have now in either case. At this point on the car, I still have to do the fuel system and the wiring so either route logisitcally would be the same. Anybody know the weight difference between a iron headed SBC and an LS1? What would you guys do if you had the choice?

StanIROCZ View Member Profile	Feb 22 2011, 10:08 PM Post #2
Veteran Member Group: Advanced Members Posts: 3,323 Joined: 30-March 06 From: Detroit Suburbs Member No.: 1,144	Another vote for LS1. It will make more power and better MPG with just a cam and valvtrain upgrades. As I understand tuning is great with the factory ECM's but no first hand experience. THe factory heads flow more than a good set of aftermarkets for a Gen1. Do you have just a spare long block or do you have the harness and ECM for the LS1?